Control indications for slotted wireless communication

ABSTRACT

Multiple control indications are transmitted within timeslots defined for a slotted communication system. For example, a wireless node may transmit a control indication at a beginning of a timeslot and at an end of a timeslot. A control indication may comprise a resource utilization message that a node generates in an attempt reduce inference at the node that is caused by transmissions by neighboring nodes. A node also may synchronize to a received timeslot of another node based on the position of one or more control indications within the timeslot. Here, each control indication may include information that indicates the position of the control indication within the timeslot.

BACKGROUND

1. Field

This application relates generally to wireless communication, and morespecifically but not exclusively to the use of multiple controlindications in wireless communication timeslots.

2. Background

Various network topologies may be employed to establish wirelesscommunication. For example, a wide area network, a local area network,or some other type of network may be deployed depending on the desiredwireless communication capabilities.

A wireless wide area network is typically a planned deployment within alicensed frequency band. Such a network may be designed to optimizespectral efficiency and quality of service to support a large number ofusers. A cellular network is one example of a wireless wide areanetwork.

A wireless local area network is often deployed without centralizedplanning. For example, such a network may be deployed in an ad hocmanner in unlicensed spectrum. Consequently, this type of network may beused to support a single user or a small number of users. A Wi-Finetwork is one example of a wireless local area network.

In practice, each of the above networks has various disadvantages due totradeoffs that may be made to provide a given type of service. Forexample, due to the complexity of centralized planning, setting up awireless wide area network may be relatively expensive and timeconsuming. Hence, such a scheme may not be well suited for “hot spot”deployments. On the other hand, an ad hoc wireless local area networkmay not achieve the same level of spatial efficiency (bits/unit area) asa planned network. Moreover, to compensate for potential interferencebetween nodes in the network, an ad hoc scheme may employ interferencemitigation techniques such as carrier sense multiple access. Inpractice, however, interference mitigation techniques such as these maylead to poor utilization, limited fairness control, and susceptibilityto hidden and exposed nodes.

United States Patent Application Publication No. 2007/0105574 describesa system that may provide various advantages over certain aspects ofconventional wide area network and personal area network deployments. Insome aspects the system employs timeslot-based communication wheremultiple wireless nodes in the system may simultaneously transmit andreceive during designated timeslots.

Fair-sharing of a wireless channel in the system is facilitated by jointscheduling of a transmission by a transmitter of one node and a receiverof another node through the use of a resource utilization message(“RUM”). Here, a transmitting node may request a set of resources basedon knowledge of availability in its neighborhood and a receiving nodemay grant some or all of the requested channels based on knowledge ofavailability in its neighborhood. For example, the transmitting nodesmay learn of availability by listening to receiving nodes in itsvicinity and the receiving node may learn of potential interference bylistening to transmitting nodes in its vicinity. In the event thereceiving node is affected by interference from neighboring transmittingnodes the receiving node may transmit a RUM in an attempt to cause theneighboring transmitting nodes to stop their interfering transmissions.According to related aspects, RUMs may be weighted to indicate not onlythat a receiving node is disadvantaged (e.g., due to the interference itsees while receiving) and desires a collision avoidance mode oftransmission, but also the degree to which the receiving node isdisadvantaged.

A transmitting node that receives a RUM may utilize the fact that it hasreceived a RUM, as well as the weight thereof, to determine anappropriate response. For example, the transmitting node may elect toabstain from transmitting, it may reduce its transmit power during oneor more designated timeslots, or it may ignore the RUM for instance ifit has received a RUM from its own receiver that indicates its ownreceiver is more disadvantaged. The advertisement of weights may thusprovide a collision avoidance scheme that is fair to all nodes in thesystem.

SUMMARY

A summary of sample aspects of the disclosure follows. It should beunderstood that any reference to aspects herein may refer to one or moreaspects of the disclosure.

The disclosure relates in some aspects to transmitting multiple controlindications within a timeslot defined for a slotted communicationsystem. For example, a wireless node may transmit control indications ata beginning of a transmit timeslot and at an end of the transmittimeslot. In this way another wireless node that is listening forcontrol indications during its receive timeslot may receive at least oneof the control indications, even if the timeslots of the nodes are notsynchronized. For example, a receive timeslot of a first node maycommence some time after the commencement of a transmit timeslot of asecond node. In this case, even though the first node may not receive acontrol indication that the second node transmitted at the beginning ofits transmit timeslot, the first node may receive a control indicationthat the second node transmitted at the end of its transmit timeslot.

In some aspects a control indication comprises an interferencemanagement message and/or a resource management message. For example, acontrol indication may take the form of a RUM that a node transmits inan attempt to reduce the interference it experiences during receiveoperations, where the interference is believed to be caused bytransmissions of neighboring nodes. At a basic level a RUM may simplyindicate that a RUM-sending node is disadvantaged in some way. Inaddition, the RUM may include an indication as to the extent to whichthe RUM-sending node is disadvantaged (e.g., the degree to whichreception of data at the RUM-sending node is falling below an expectedor desired level).

Each of the neighboring nodes is configured to regularly scan for RUMsand determine, based on the RUMs, whether to limit transmission during asubsequent timeslot. For example, if a given RUM-sending node is moredisadvantaged than a RUM-sending node currently associated with aparticular RUM-receiving node, that RUM-receiving node may abstain fromtransmitting or transmit at a lower power level during an upcomingtimeslot so that the more disadvantaged RUM-sending node may moreeffectively receive its data during that timeslot.

The disclosure relates in some aspects to synchronizing to a timeslot ofanother node (e.g., referred to herein, for convenience, as a receivedtimeslot) based on a position of one or more control indications withinthe received timeslot. Here, a control indication may compriseinformation that is indicative of the position of the control indicationwithin the received timeslot. For example, the information may indicatethat the control indication is near a beginning or an end of thereceived timeslot. A node that receives the timeslot, and hence thecontrol indications, may thereby readily synchronize its timeslots tothe received timeslot since the node will have information indicative ofthe timing of the beginning and/or end of the received timeslot.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of the disclosure willbe more fully understood when considered with respect to the followingdetailed description, appended claims, and accompanying drawings,wherein:

FIG. 1 is a simplified diagram of several sample aspects of a wirelesscommunication system;

FIG. 2, including FIGS. 2A and 2B, is a simplified diagram of severalsample aspects of slotted communication;

FIG. 3 is a simplified diagram of several sample aspects of asynchronousslotted communication;

FIG. 4 is a simplified diagram of several sample aspects of a timeslot;

FIG. 5 is a simplified timing diagram of several sample aspects ofsynchronous slotted communication;

FIG. 6 is a simplified timing diagram of several sample aspects ofasynchronous slotted communication;

FIG. 7 is a simplified timing diagram of several sample aspects ofasynchronous slotted communication;

FIG. 8 is a simplified block diagram of several sample aspects of aslotted communication system;

FIG. 9 is a flowchart of several sample aspects of operations that maybe performed to transmit information in a slotted communication system;

FIG. 10 is a flowchart of several sample aspects of operations that maybe performed to receive information in a slotted communication system;

FIG. 11 is a simplified block diagram of several sample aspects ofcommunication components; and

FIG. 12 depicts simplified block diagrams of several sample aspects ofapparatuses adapted to provide slotted communication.

In accordance with common practice the various features illustrated inthe drawings may not be drawn to scale. Accordingly, the dimensions ofthe various features may be arbitrarily expanded or reduced for clarity.In addition, some of the drawings may be simplified for clarity. Thus,the drawings may not depict all of the components of a given apparatus(e.g., device) or method. Finally, like reference numerals may be usedto denote like features throughout the specification and figures.

DETAILED DESCRIPTION

Various aspects of the disclosure are described below. It should beapparent that the teachings herein may be embodied in a wide variety offorms and that any specific structure, function, or both being disclosedherein is merely representative. Based on the teachings herein oneskilled in the art should appreciate that an aspect disclosed herein maybe implemented independently of any other aspects and that two or moreof these aspects may be combined in various ways. For example, anapparatus may be implemented or a method may be practiced using anynumber of the aspects set forth herein. In addition, such an apparatusmay be implemented or such a method may be practiced using otherstructure, functionality, or structure and functionality in addition toor other than one or more of the aspects set forth herein.

As an example of the above, in some aspects a method for wirelesscommunication comprises defining timeslots for slotted communication andtransmitting, in each of at least one portion of the timeslots, data andat least two instances of a control indication, wherein each instance ofthe control indication is independently encoded and transmitted. Here,in some aspects each control indication may comprise a resourceutilization message while in other aspects each control indication maycomprise information that facilitates synchronization with thetimeslots.

FIG. 1 illustrates several sample aspects of a wireless communicationsystem 100. The system 100 includes several wireless nodes, generallydesignated as nodes 102 and 104. A given node may receive one or moretraffic flows, transmit one or more traffic flows, or both. For example,each node may comprise at least one antenna and associated receiver andtransmitter components. In the discussion that follows the termreceiving node may be used to refer to a node that is receiving and theterm transmitting node may be used to refer to a node that istransmitting. Such a reference does not imply that the node is incapableof performing both transmit and receive operations.

In some implementations a node may comprise an access terminal, a relaypoint, or an access point. For example, the nodes 102 may compriseaccess points or relay points and the nodes 104 may comprise accessterminals. In a typical implementation the access points 102 provideconnectivity for a network (e.g., a Wi-Fi network, a cellular network, aWiMax network, a wide area network such as the Internet, and so on). Arelay point 102 may provide connectivity to another relay point or to anaccess point. For example, when an access terminal (e.g., accessterminal 104A) is within a coverage area of a relay point (e.g., relaypoint 102A) or an access point (e.g., access point 102B), the accessterminal 104A may be able to communicate with another device connectedto the system 100 or some other network.

In some aspects the system 100 may employ slotted communication. Forexample, communication between nodes in the system 100 may beaccomplished through the use of designated timeslots. In general, theteachings herein may relate to improvements in asynchronous slottedcommunication. In addition, these teachings also may be applicable tosynchronous slotted communication and other forms of communication.

FIG. 2 illustrates a simplified example of traffic flow associated withtransmit timeslots and receive timeslots. Referring to FIG. 2A, in thisexample one flow of traffic is from a node A (e.g., node 104A in FIG. 1)to a node B (e.g., node 102A) and then to a node C (e.g., node 102B).Each of the nodes A, B, and C are allowed to transmit or to receiveduring certain timeslots. For example, referring to FIG. 2B, nodes A andC transmit during odd numbered timeslots and node B transmits duringeven numbered timeslots. Conversely, nodes A and C receive during evennumbered timeslots and node B receives during odd numbered timeslots. Asillustrated by the relative alignment of the timeslots of FIG. 2B, thetimeslots for the nodes A, B, and C are synchronized.

The use of timeslots as described in FIG. 2B may provide increasedspectral efficiency and reduce the amount of interference in a wirelesssystem. For example, if the nodes that transmit during the same timeslotare spaced a sufficient distance apart they may be able to successfullytransmit to their receiving nodes without causing undue interference atother receiving nodes.

Moreover, interference management techniques may be employed to furtherreduce the possibility of interference between nodes. As will bediscussed in more detail below, the nodes in the system may transmitcontrol indications that are used to reduce the amount of interferenceseen by a given node. For example, a node that is experiencinginterference when it is trying to receive data from a particular nodemay transmit a control indication requesting that other nodes refrainfrom transmitting or reduce their transmit power when the receiving nodeis receiving data. To this end, nodes that have data to transmit areconfigured to regularly scan for such control indications from nodesthat are expecting to receive data.

As mentioned above, in FIG. 2B the timeslots for nodes A, B, and C aresynchronized in that the timeslots commence and end at the same time. Insuch an implementation, a specific period of time within a timeslot maybe designated for the transmission of a control indication. In thiscase, nodes that have data to transmit may scan for control indicationsat the designated period of time during a timeslot to determine whetherany receiving nodes are requesting transmitting nodes to limit theirtransmissions. This method of interference avoidance may be employedacross a synchronous system. That is, any node in the synchronous systemmay monitor for control indications at the designated times to readilydetermine whether there are any associated or non-associated receivingnodes that are requesting the transmitting nodes to limit theirtransmissions.

In contrast, in asynchronous implementations where the timeslots ofnon-associated nodes are not synchronized, the control indicationtransmitted by a node may not be readily obtained by anothernon-associated node. For example, in an asynchronous system thetimeslots for a set of nodes A and D may not commence and end at thesame time. Hence, if node A transmits a control indication at thebeginning of its timeslot, node D may not receive the control indicationif its receive timeslot commences at a later point in time.

Referring to FIG. 3, in some aspects a node may be configured totransmit several instances of a control indication during a transmittimeslot 302 to facilitate reception of the control indication during areceive timeslot 304 of another node. For example, node A may transmitcontrol indications 306 and 308 near the beginning and the end of thetimeslot 302, respectively. In this case, although node D will notreceive the control indication 306 during its receive timeslot 304, nodeD will receive the control indication 308. In this case, however, node Dmay not know exactly when the control indication is being transmitteddue to the asynchronous timing between the nodes. Consequently, node Dmay be configured to scan during its entire receive timeslot 304 toacquire the control indication.

In general, control indications may be transmitted at any time duringthe transmit timeslot. In a typical implementation a node transmits afirst instance of a control indication near (e.g., at or close to) thebeginning of the transmit timeslot and then transmits a second instanceof the control indication near the end of the transmit timeslot. In thisway, a node that is close enough to receive this information may be ableto receive the control indication over a wide range of timing offsetsbetween the transmit and receive timeslots. For example, if theinstances of the control indication are transmitted at the beginning andthe end of the transmit timeslot and the control indication isrelatively short in duration, a receive timeslot that barely overlapsthe transmit timeslot in time may still enable reception of the controlindication.

In some aspects a node may use a received control indication tosynchronize that node's receive or transmit timeslots with the transmittimeslots of another node. For example, the node that received thecontrol indication may utilize information regarding the location of thecontrol indication within the transmit timeslot to determine when thetransmit timeslot begins and ends. This node may then adjust its receiveor transmit timeslot to begin and end at the same time as the transmittimeslot.

In some implementations a control indication includes information thatis indicative of the location of the control indication within thetransmit timeslot. For example, a first instance of a control indicationmay include information that indicates that it is near (e.g., at) thebeginning of the timeslot. Similarly, a second instance of the controlindication may include information that indicates that it is near (e.g.,at) the end of the timeslot.

Additional examples of the use of multiple control indications in atimeslot will be discussed in conjunction with FIGS. 4-7. These figuresillustrate, in a simplified manner, various signal timing relationshipsof nodes that use a request/grant scheme and control indications toefficiently share a communication medium.

FIG. 4 illustrates a sample format for a timeslot 400. Nodes may thuscommunicate over a given frequency band by transmitting and receivingdata at defined timeslot intervals according to the timeslot structure.A control channel 402 is defined at the beginning of the timeslot 400.The control channel 402 is followed by a data channel designated by theblocks 404 labeled with the letter “D.” Another control channel 406follows a first portion of the data channel 404. Finally, a controlchannel 408 is defined at the end of the timeslot 400. In general, thecontrol indication referenced herein may comprise any information thatmay be transmitted over one or more control channels. Such informationmay comprise a portion of a message, an entire message or multiplemessages.

In some implementations guard bands are defined between various channelsof the timeslot. FIG. 4 illustrates an example where one guard band isdefined between the control channel 402 and the data channel 404 andanother guard band is defined between the control channel 408 and thedata channel 404. Such guard bands may be employed to enable thetimeslots to be dynamically designated as transmit timeslots or receivetimeslots. For example, when a receive timeslot is re-designated as atransmit timeslot, a node may continue to scan during one or more of thecontrol channels (e.g., to listen for RUMs). The guard band thusprovides a defined period of time within which a node may switch itstransceiver from a transmit mode to a receive mode or vice versa.

In some implementations multiple timeslot channels may be establishedover different frequency bands. In this way, the nodes in a system maysimultaneously transmit and/or receive data via several timeslotchannels. In addition, in some implementations a separate controlchannel may be established over another (e.g., dedicated) frequencyband. Such a control channel may have a relatively low reuse factor(e.g., ¼ or smaller) to reduce the impact of any potential interferenceon the control information.

It should be appreciated that the timeslot 400 is but one example of asuitable timeslot structure. Thus, the teachings herein are applicableto various forms of slotted communication that may employ, for example,different types of timeslot structures, differing timeslot lengths,various types of data channels and control channels, and various timedivision multiplexing and frequency division multiplexing schemes.

Sample functionality relating to the use of the channels of the timeslot400 will now be described in conjunction with FIGS. 5-7. To simplify theinitial discussion relating to the request/grant scheme, several basicconcepts will be treated in the context of a synchronous system asrepresented by FIG. 5. In addition, for convenience the discussion thatfollows may simply refer to the use of RUMs. It should be appreciated,however, that other forms of control indications may be applicable hereas well.

FIG. 5 depicts timing relating to two pairs of nodes, nodes A and B andnodes C and D. Nodes A and B are associated with one another to enablenode A to transmit to node B, and vice versa. Similarly, nodes C and Dare associated with one another to enable node C to transmit to node D,and vice versa. FIG. 5 further illustrates that the timeslots ofassociated nodes A and B are synchronized with the timeslots ofassociated nodes C and D.

The nodes may be configured to alternately communicate via timeslots ina similar manner as described above in conjunction with FIG. 2. In thiscase, nodes A and C transmit during even numbered timeslots and receiveduring odd numbered timeslots. Conversely, nodes B and D receive duringeven numbered timeslots and transmit during odd numbered timeslots.

The nodes employ a request/grant scheme to control when a node isallowed to transmit data. For example, when node A wishes to transmitdata to node B, node A transmits a request during one of its transmittimeslots (e.g., timeslot 2). This message may comprise a request totransmit over one or more channels. In the timeslot example of FIG. 4,this request may be sent via the control channel 406.

Node B receives the request during its corresponding receive timeslot.In response to the request, node B may transmit a grant (“GNT”) duringone of its transmit timeslots (e.g., timeslot 3). Here, node B may grantall or a subset of the channels requested by node A. For example, node Bmay not grant channels that have recently exhibited a relatively highlevel of interference. In the example of FIG. 4, this grant may be sentvia the control channel 402.

In some aspects, in conjunction with the above operations node A maytransmit a pilot message (e.g., a signal having a known signalstrength). Node B may use the pilot message to determine at rate atwhich node A should transmit its data. In some implementations node Bsends this rate information to node A with the grant.

After receipt of the grant during its corresponding receive timeslot,node A transmits the data (e.g., via the data channel 404 of FIG. 4)during one of its transmit timeslots (e.g., timeslot 4). Node B willthus receive the data during its corresponding receive timeslot.

In practice, the nodes may be in relatively close proximity to oneanother such that transmissions by a node of one node pair may interferewith reception by a node of the other node pair. Accordingly, the nodesalso employ an interference management scheme whereby a node that isexperiencing degradation in service due to interfering transmissionsfrom one or more nearby transmitting nodes may send out a controlindication that requests that the transmitting nodes limit theirtransmissions.

In some implementations the control indication comprises a RUM. Briefly,each node that is experiencing degradation in service may transmit a RUMduring one of its transmit timeslots (e.g., timeslot 1). Such a node maybe referred to herein as a RUM-sending node. Any nearby node thatreceives during this timeslot (e.g., the nodes that transmit during evennumbered timeslots) may potentially receive the RUM transmitted by eachRUM-sending node. Such a node may be referred to herein as aRUM-receiving node. Each RUM-receiving node may then make a decision asto whether to limit its transmissions based on all of the RUMs itreceives. As will be discussed in more detail below, each RUM mayinclude weight information that may be used to determine whichRUM-sending node is more disadvantaged.

Referring to the specific example of FIG. 5, both nodes B and D maytransmit RUMs during a defined time period within timeslot 1. Forexample, the shaded portion at the beginning of each timeslot mayrepresent the timing of a control channel for the timeslot. A node thatreceives during timeslot 1 (e.g., node A) may thus be configured to scanfor RUMs during this time period. Upon receipt of the RUMs from nodes Band D, nodes A and C may determine that node B is more disadvantagedthan node D. In other words, node B may be designated as the winner ofthis particular contention for resources and node D designated as theloser. As will be discussed in more detain below, this determination maybe based on a comparison of information from each RUM that is indicativeof a degree to which data reception at a node is being adverselyaffected by interfering transmissions from at least one other node.

In the event node D does not win the contention for resources, itsassociated transmitting node (node C) may limit its planned transmissionfor timeslot 4. For example, as shown in FIG. 5 node C may abstain fromsending a request in timeslot 2 to transmit data to node D.

Conversely, since node B won the contention for resources, itsassociated transmitting node (node A) will send a request in timeslot 2to initiate transmission of data in timeslot 4. Advantageously, due tothe lack of a corresponding request in timeslot 2 from node C, therewill not be any potentially interfering transmissions from node C duringtimeslot 4. Additional details relating to the generation andcharacteristics of RUMs and associated operations will be discussedlater in this disclosure.

As noted above, FIG. 5 relates to a synchronous system where thetimeslots for nodes A-D are aligned. Additional aspects of the use ofmultiple control indications where the timeslots of different sets ofnodes are not time aligned (e.g., as in an asynchronous system) will nowbe discussed in conjunction with FIGS. 6 and 7.

In FIGS. 6 and 7 the timeslots (e.g., timeslot 1′) for nodes C and D areoffset in time from the timeslots (e.g., timeslot 1) for nodes A and B.Consequently, any control indications (e.g., RUMs) transmitted by node Bat the beginning of timeslot 1, will not be received by node C since itsreceive timeslot, timeslot 1′, starts at a later point in time.Consequently, in accordance with the teachings herein, the nodes may beconfigured to transmit several control indications during a giventransmit timeslot. For example, the nodes may transmit one instance of aRUM during the control channel 402 (FIG. 4) at the beginning of thetimeslot and transmit another instance of the RUM during the controlchannel 408 at the end of the timeslot.

As mentioned above, the nodes also may be configured to scan for RUM forthe entirety of their receive timeslots. Here, since the receivetimeslot of node A is time aligned with the transmit timeslot of node B,node A will receive both instances of the RUM from node B. In contrast,node C listens for RUMs during timeslot 1′. Accordingly, node C will notbe receiving when node B transmits the first instance of the RUM. Node Cwill, however, receive the second instance of the RUM. In a similarmanner, node C will receive both instances of the RUM transmitted bynode D and node A will receive the first instance of the RUM transmittedby node D but not the second instance.

Assuming again that node B is more disadvantaged than node D, node Awill send its request in timeslot 2 and node C may abstain from sendingits request in timeslot 2′. In this case, there will not be interferingtransmissions from node C during the beginning portion of timeslot 4′that overlaps with timeslot 4.

FIG. 7 illustrates a similar example for transmission from node D tonode C. In this case, node D will receive both instances of the RUMsfrom node C and the first instance of the RUM from node B (duringtimeslot 0′). Consequently, node D may abstain from sending its requestin timeslot 1′. In this case, there will not be interferingtransmissions from node D during the latter portion of timeslot 3′ thatoverlaps with timeslot 4.

With the above overview in mind, additional details of sample structureand operations of wireless nodes will now be discussed in conjunctionwith FIGS. 8-10. FIG. 8 depicts a communication system 800 includingseveral operational components 802 and 804 that may be respectivelyemployed to transmit and receive via a wireless communication link 806.FIG. 9 depicts several operations that may be performed in conjunctionwith transmit operations. FIG. 10 depicts several operations that may beperformed in conjunction with receive operations. For convenience, theoperations of FIGS. 9 and 10 (or any other operations discussed ortaught herein) may be described as being performed by specificcomponents such as those described in system 800. It should beappreciated, however, that these operations may be performed by othertypes of components and may be performed using a different number ofcomponents. It also should be appreciated that one or more of theoperations described herein may not be employed in a givenimplementation.

The operations of FIGS. 9 and 10 relate to the generation andtransmission of a control indication by a receiving node (e.g., node B,timeslot 1 in FIG. 6) and the reception of the control indication by atransmitting node (e.g., node C, timeslot 1′ in FIG. 6). Here, thedesignations transmitting node and receiving node are based on the datatransfer operations of timeslot 4. Based on the received controlindication and possibly other control indications, the transmitting nodedetermines whether to limit one or more subsequent transmissions or,optionally, synchronizes with the timeslots of the receiving node.

Referring to FIG. 9, as represented by block 902, at some point prior tocommencement of traffic flow in the system 800, transmit timeslots aredefined for the receiving node 802. This may involve, for example,selecting which timeslots a given node will use for transmitting. Inaddition, in a synchronous system the timeslots of the node 802 may besynchronized with the timeslots of one or more non-associated nodes(e.g., other nodes that are associated with the same access point asnode 802). In some implementations the definition of the transmittimeslots may be built into the hardware and/or the code for the node802. For example, the node 802 may determine which mode it is operatingin and then set the timing for the timeslots based on the mode. Here,the timeslot definition may be a function of an operating communicationfrequency. Accordingly, defining a timeslot may comprise variousoperations including, but not limited to, establishing predeterminedtimeslots, preprogramming timeslot-related functionality, performingoperations on-line or off-line, providing static or dynamic timeslots,and the operation of hardware, code or both. These and other relatedoperations may be performed by a transmit timeslot definer component808. In some implementations these operations may involve communicatingvia a transmitter 814 and a receiver 816 of a transceiver 818 withanother node. For example, the node 802 may cooperate with an accesspoint that manages a wireless network to define the timeslots.

At block 904 a control indication generator 810 determines whether togenerate a control indication. As discussed herein, the controlindication may comprise a RUM, a synchronization indication, or both.

In some aspects the operations of block 904 may involve determiningwhether one or more traffic flows being received at the node 802 aremeeting a quality of service (“QoS”) target. Here, quality of servicemay relate to, for example, throughput, latency, spectral efficiency,data rate, interference, or some other suitable parameter.

For example, in an ad hoc deployment of wireless nodes, acarrier-to-interference ratio (“C/I”) may be undesirably low at somenodes. It will be appreciated that interference levels employed tocalculate C/I may comprise noise, such that C/I may similarly beexpressed as C/(I+N), where N is noise.

A receiving node may manage such interference by requesting that certaintransmitting nodes in the vicinity either reduce their respectivetransmission powers or back off completely from the indicated channels.Accordingly, at block 906 the control indication generator 810 maygenerate an appropriate control indication based on a determination atblock 904 that a quality of service level is not being met. In someaspects a determination of whether a desired quality of service level ismet may be a function of, for instance, a ratio of a target quality ofservice value to an actual quality of service value for a given node.For the above C/I example, the indication may identify all of thechannels (e.g., in a multi-channel system) that exhibit a C/I that isbelow a defined threshold.

To ensure that interference avoidance happens in a fair manner, that is,to ensure that all nodes get a fair share of transmission opportunities,a RUM may comprise node weight information. In some aspects, the weightrepresents the degree of disadvantage that the node is experiencing andis used in managing the fairness of the channel access between a set ofinterfering nodes contending for a common resource. The level ofdisadvantage may be determined as a function of a level of receivedservice at the node, which may be impacted by various parameters such aslatency, IOT, C/I, throughput, data rate, spectral efficiency, and soon.

A RUM may thus be broadcast by a node when interference levels on thenode's desired receive channels exceed defined threshold level. As anexample, if throughput is used to measure the degree of disadvantage,then one possible relationship may be represented as:

$\begin{matrix}{{{RUM}\mspace{14mu}{Weight}} = {Q\left( \frac{R_{target}}{R_{actual}} \right)}} & {{EQUATION}\mspace{14mu} 1}\end{matrix}$where Rtarget represents the desired throughput, R_(actual) is theactual throughput being achieved, and Q(x) represents the quantizedvalue of x. When there is a single flow at the receiving node, Rtargetmay represent the minimum desired throughput for that flow andR_(actual) may represent the average throughput that has been achievedfor that flow.

A RUM also may comprise a channel bit mask that indicates the channelsto which the RUM applies. In some implementations the channel bit maskmay be used to provide an additional dimension to realize collisionavoidance, which may be useful when a receiving node needs to schedule asmall amount of data over a portion of a channel (e.g., when a timeslotdefines multiple data channels) and does not want a transmitting node tocompletely back off from the entire channel. This aspect may providefiner granularity in the collision avoidance mechanism, which may beimportant for bursty traffic.

In some implementations the number of channels designated by the RUM maybe selected based on the level of disadvantage. For example, for agreater disadvantage, a greater number of channels may be selected.

In general, a weight may be defined in a variety of ways and may bebased on various criteria. In some aspects a weight may be based ondynamic criteria. For example, as mentioned above a weight may reflectthe current conditions of one or more traffic flows associated with anode. In some implementations a weight may correspond to the flow beingcarried (e.g., received) at that node that is most disadvantaged. Insome implementations a weight may be based on more than one flow.

In some aspects a weight may be based on static criteria. For example, agiven node may be assigned a weight that is added to other weightparameters. In this way additional priority may be provided for selectednodes.

The quality of service and corresponding disadvantage may be repeatedlyreassessed over time to determine whether the node's quality of servicehas improved. Based on the measured quality of service, the weight andthe number of channels for which a subsequent RUM is transmitted maythus be adjusted. For instance, if the node's quality of service did notimprove or has worsened, to improve the level of service received at thenode the weight may be increased or the number of channels for which asubsequent RUM is transmitted may be increased. If the node's quality ofservice has improved, then the weight may be decreased and the number ofchannels for which a subsequent RUM is transmitted may be reduced toconserve resources.

As represented by block 908, the node 802 generates or otherwise obtainsany other information that is to be transmitted during a timeslot. Forexample, the node may provide data 812 to be transmitted by generatingthe data or retrieving data from a memory device. In addition, the nodemay generate or otherwise provide control information (e.g., dataacknowledgements) to be transmitted during a timeslot.

As represented by block 910, the transmitter 814 transmits the data andcontrol information at the appropriate times during the transmittimeslot. As discussed above, this may include transmitting first andsecond instances of a control indication near a beginning and an end ofthe timeslot, respectively. For example, the transmitter 814 may encodethe control indication generated at block 906 and transmit the encodedindication at the beginning of a designated transmit timeslot. Thetransmitter 814 may then encode the data and other information providedat block 908 and transmit this encoded data and information followingthe first instance of the control indication. Next, the transmitter 814may again encode the control indication generated at block 906 andtransmit this encoded indication at the end of the designated transmittimeslot. Thus, in this example the node transmits multiple instances ofa control indication where each instance of the control indication isindependently encoded and transmitted. In some implementations theencoded indications may be identical or substantially identical. In someimplementations the encoded indications may be different (e.g., due tothe inclusion of different synchronization information). It should beappreciated that the above techniques also may be used to transmit morethan two instances of a control indication, if desired. In addition,depending on the timeslot control structure control indications may notbe transmitted in every transmit timeslot.

In some aspects all of the RUMs in a system (e.g., a given network) maybe transmitted at a constant power spectral density (“PSD”) or at aconstant power. This may be the case regardless of the normal transmitpower of the node. In this way, RUMs may be received at potentiallyinterfering (e.g., higher power) transmitting nodes that are relativelyfar away, irrespective of whether the RUM-sending node is a lower powernode or a higher power node. In other words, the RUM decoding range maybe designed to be substantially equal to or greater than the largesttransmit interference range to be controlled by the system.

Referring now to FIG. 10, as represented by block 1002, receivetimeslots are defined for the node 804. This may involve, for example,operations that are similar to the operations of block 902. To this endthe node 804 may include a receive timeslot definer component 820. Thetimeslot definer 820 synchronizes the receive timeslots of node 804 withthe transmit timeslots of any associated nodes (e.g., node 802). Inaddition, in a synchronous system the node 804 may be configured tosynchronize its receive timeslots with transmit timeslots of anon-associated node (e.g., as discussed below at block 1010).

As represented by block 1004, a receiver component 822 of a transceiver824 may receive, during a given receive timeslot, signals associatedwith a transmit timeslot of the node 802. For example, in anasynchronous configuration the receive timeslot of node 804 may overlaponly a portion of the transmit timeslot of node 802 (e.g., as shown inFIG. 6).

As represented by block 1006, a processor 826 may be configured toprocess the signals received over the entire receive timeslot to extractat least one instance of a control indication that was transmittedduring a transmit timeslot. Referring again to the example of FIG. 6,the node C may receive the second instance of the RUM transmitted bynode B during a given timeslot. As mentioned above, the controlindication may comprise a RUM, a synchronization indication, or both.

As represented by block 1008, a timeslot transmission limiter 828 maydetermine, based on one or more received control indications whether tolimit a future transmission by a transmitter 834 of the node 804. Forexample, the timeslot transmission limiter 828 may cause the node 804 toabstain from transmitting or reduce its transmit power. In the formercase, the node 804 may not send a request to transmit (e.g., see node Cin FIG. 6). In the latter case, the node 804 may determine whether thereis an acceptable level of transmit power that will not causeinterference at a RUM-sending node (e.g., node 802).

In conjunction with the above, an interference determiner 830 maydetermine whether there is a possibility that the node 804 willinterfere with receive operations of a RUM-sending node. As mentionedpreviously, a RUM may be sent at a constant power spectral density(“PSD”) or at a constant power. A RUM-receiving node (e.g., node 804)may thus estimate a radio frequency (“RF”) channel gain between itselfand the RUM-sending node based on the received power spectral densityand/or the received power of the RUM and based on knowledge of the powerspectral density and/or the power at which the RUM was transmitted. Inthis way, the RUM-receiving node may determine whether it will causeinterference at the RUM-sending node if it transmits. Such adetermination may involve, for example, determining whether theestimated level of interference is above a defined acceptable thresholdlevel.

There may thus be situations wherein a RUM-receiving node is able todecode the RUM from the RUM-sending node, but determines that it willnot cause interference. For example, a low power node may not limitfuture transmissions since its transmissions may not be strong enough tocause interference at the RUM-sending node.

In some aspects determining whether to limit a future transmission bythe node 804 involves prioritizing the relative disadvantage of eachRUM-sending node. For example, if several nodes are disadvantaged, eachof these nodes may send a RUM. In this case, a node that receives theseRUMs may use some criterion or criteria to determine whether any of thenodes has a higher priority (e.g., a greater disadvantage) than one ormore other nodes.

In some aspects this determination involves comparing weights associatedwith each of the RUMs. In one example, the RUM-sending node associatedwith the highest weight may be designated as node with highest priority(e.g., the winning node in FIGS. 6 and 7).

Next, the RUM-receiving node determines whether a node with priority isan associated node. Here, the RUM-receiving node will not limit itstransmission if the node it transmits to (e.g., its associated node) isthe winning node. Conversely, if some other node is the winning node,the RUM-receiving node may limit its transmissions as discussed herein.

In some aspects the timeslot transmission limiter 828 may identify aportion of a transmit timeslot of the node 804 for which transmissionwill be limited (e.g., corresponding to a portion of a receive timeslotof another node that is subject to interference). For example, referringto FIG. 6 only the first half of the timeslot 4′ overlaps with timeslot4. Accordingly, the timeslot transmission limiter 828 may elect to onlylimit transmissions during this portion of timeslot 4′ to reduce thepotential interference with receptions during timeslot 4. In someaspects this may involve determining the timing of the transmit timeslotrelative to the receive timeslot. This timing information may beobtained, for example, based on at least one of the instances of thecontrol indication. For example, as is described in more detail inconjunction with block 1010, one or more instances of a controlindication may include information indicative of its location relativeto the beginning and/or the end of the transmit timeslot.

As represented by block 1010, in some implementations a node mayoptionally synchronize its timeslots with the timeslots of another node.For example, a node may elect to synchronize with another node in anattempt to achieve an improvement in communication performance (e.g.,higher channel capacity and improved quality of service). To accomplishsynchronization, the node 804 may include a timeslot synchronizer 832that is configured to determine the timing of timeslots of another nodeand adjust the timeslots of the node 804 accordingly.

In some aspects synchronization may be achieved through the use ofreceived control indications. For example, a control indication mayinclude information indicative of the location of the control indicationwithin a timeslot. The node 804 may then use this information tosynchronize to the timeslot. For example, if a control indication islocated at the beginning or the end of the timeslot, the controlindication may comprise a synchronization indication of thisrelationship. The node 804 may then readily synchronize to the timeslotsince the node 804 can then determine the times of the beginning or theend of the timeslot based on the timing of the control indication.

The teachings herein may be incorporated into a device employing variouscomponents for communicating with at least one other wireless device.FIG. 11 depicts several sample components that may be employed tofacilitate communication between devices. Here, a first device 1102(e.g., an access terminal) and a second device 1104 (e.g., an accesspoint) are adapted to communicate via a wireless communication link 1106over a suitable medium.

Initially, components involved in sending information from the device1102 to the device 1104 (e.g., a reverse link) will be treated. Atransmit (“TX”) data processor 1108 receives traffic data (e.g., datapackets) from a data buffer 1110 or some other suitable component. Thetransmit data processor 1108 processes (e.g., encodes, interleaves, andsymbol maps) each data packet based on a selected coding and modulationscheme, and provides data symbols. In general, a data symbol is amodulation symbol for data, and a pilot symbol is a modulation symbolfor a pilot (which is known a priori). A modulator 1112 receives thedata symbols, pilot symbols, and possibly signaling for the reverselink, and performs modulation (e.g., OFDM or some other suitablemodulation) and/or other processing as specified by the system, andprovides a stream of output chips. A transmitter (“TMTR”) 1114 processes(e.g., converts to analog, filters, amplifies, and frequency upconverts)the output chip stream and generates a modulated signal, which is thentransmitted from an antenna 1116.

The modulated signals transmitted by the device 1102 (along with signalsfrom other devices in communication with the device 1104) are receivedby an antenna 1118 of the device 1104. A receiver (“RCVR”) 1120processes (e.g., conditions and digitizes) the received signal from theantenna 1118 and provides received samples. A demodulator (“DEMOD”) 1122processes (e.g., demodulates and detects) the received samples andprovides detected data symbols, which may be a noisy estimate of thedata symbols transmitted to the device 1104 by the other device(s). Areceive (“RX”) data processor 1124 processes (e.g., symbol demaps,deinterleaves, and decodes) the detected data symbols and providesdecoded data associated with each transmitting device (e.g., device1102).

Components involved in sending information from the device 1104 to thedevice 1102 (e.g., a forward link) will be now be treated. At the device1104, traffic data is processed by a transmit (“TX”) data processor 1126to generate data symbols. A modulator 1128 receives the data symbols,pilot symbols, and signaling for the forward link, performs modulation(e.g., OFDM or some other suitable modulation) and/or other pertinentprocessing, and provides an output chip stream, which is furtherconditioned by a transmitter (“TMTR”) 1130 and transmitted from theantenna 1118. In some implementations signaling for the forward link mayinclude power control commands and other information (e.g., relating toa communication channel) generated by a controller 1132 for all devices(e.g. terminals) transmitting on the reverse link to the device 1104.

At the device 1102, the modulated signal transmitted by the device 1104is received by the antenna 1116, conditioned and digitized by a receiver(“RCVR”) 1134, and processed by a demodulator (“DEMOD”) 1136 to obtaindetected data symbols. A receive (“RX”) data processor 1138 processesthe detected data symbols and provides decoded data for the device 1102and the forward link signaling. A controller 1140 receives power controlcommands and other information to control data transmission and tocontrol transmit power on the reverse link to the device 1104.

The controllers 1140 and 1132 direct various operations of the device1102 and the device 1104, respectively. For example, a controller maydetermine an appropriate filter, reporting information about the filter,and decode information using a filter. Data memories 1142 and 1144 maystore program codes and data used by the controllers 1140 and 1132,respectively.

FIG. 11 also illustrates that the communication components may includeone or more components that perform timeslot-related operations astaught herein. For example, a timeslot control component 1146 maycooperate with the controller 1140 and/or other components of the device1102 to send and receive signals to another device (e.g., device 1104)in accordance with defined timeslots as taught herein. Similarly, atimeslot control component 1148 may cooperate with the controller 1132and/or other components of the device 1104 to send and receive signalsto another device (e.g., device 1102) in accordance with definedtimeslots.

The teachings herein may be incorporated into (e.g., implemented withinor performed by) a variety of apparatuses (e.g., devices). For example,each node may be configured, or referred to in the art, as an accesspoint (“AP”), NodeB, Radio Network Controller (“RNC”), eNodeB, BaseStation Controller (“BSC”), Base Transceiver Station (“BTS”), BaseStation (“BS”), Transceiver Function (“TF”), Radio Router, RadioTransceiver, Basic Service Set (“BSS”), Extended Service Set (“ESS”),Radio Base Station (“RBS”), or some other terminology. Certain nodesalso may be referred to as subscriber stations. A subscriber stationalso may be known as a subscriber unit, a mobile station, a remotestation, a remote terminal, an access terminal, a user terminal, a useragent, a user device, or user equipment. In some implementations asubscriber station may comprise a cellular telephone, a cordlesstelephone, a Session Initiation Protocol (“SIP”) phone, a wireless localloop (“WLL”) station, a personal digital assistant (“PDA”), a handhelddevice having wireless connection capability, or some other suitableprocessing device connected to a wireless modem. Accordingly, one ormore aspects taught herein may be incorporated into a phone (e.g., acellular phone or smart phone), a computer (e.g., a laptop), a portablecommunication device, a portable computing device (e.g., a personal dataassistant), an entertainment device (e.g., a music or video device, or asatellite radio), a global positioning system device, or any othersuitable device that is configured to communicate via a wireless medium.

As mentioned above, in some aspects a wireless node may comprise anaccess device (e.g., a cellular or Wi-Fi access point) for acommunication system. Such an access device may provide, for example,connectivity for or to a network (e.g., a wide area network such as theInternet or a cellular network) via a wired or wireless communicationlink. Accordingly, the access device may enable another device (e.g., aWi-Fi station) to access the network or some other functionality.

A wireless node may thus include various components that performfunctions based on data transmitted by or received at the wireless node.For example, an access point and an access terminal may include anantenna for transmitting and receiving signals (e.g., control and data).An access point also may include a traffic manager configured to managedata traffic flows that its receiver receives from a plurality ofwireless nodes or that its transmitter transmits to a plurality ofwireless nodes. In addition, an access terminal may include a userinterface configured to output data received by the receiver or providedata to be transmitted by the transmitter.

A wireless device may communicate via one or more wireless communicationlinks that are based on or otherwise support any suitable wirelesscommunication technology. For example, in some aspects a wireless devicemay associate with a network or two or more wireless devices may form anetwork. In some aspects the network may comprise a local area networkor a wide area network. A wireless device may support or otherwise useone or more of a variety of wireless communication protocols orstandards including, for example, CDMA, TDMA, OFDM, OFDMA, WiMAX, Wi-Fi,or other wireless technologies. Similarly, a wireless device may supportor otherwise use one or more of a variety of corresponding modulation ormultiplexing schemes. A wireless device may thus include appropriatecomponents (e.g., air interfaces) to establish and communicate via oneor more wireless communication links using the above or other wirelesscommunication technologies. For example, a wireless device may comprisea wireless transceiver with associated transmitter and receivercomponents (e.g., transmitters 814 and 834 and receivers 816 and 822)that may include various components (e.g., signal generators and signalprocessors) that facilitate communication over a wireless medium.

The components described herein may be implemented in a variety of ways.Referring to FIG. 12, a system 1200 including apparatus 1202 andapparatus 1204 is represented as a series of interrelated functionalblocks that may represent functions implemented by, for example, one ormore integrated circuits (e.g., an ASIC) or may be implemented in someother manner as taught herein. As discussed herein, an integratedcircuit may include a processor, software, other components, or somecombination thereof.

As shown in FIG. 12, the apparatuses 1202 and 1204 may include one ormore modules 1206, 1208, 1210, 1212, 1214, 1216, 1218, and 1220 that mayperform one or more of the functions described above with regard tovarious figures. For example, an ASIC for defining 1206 may providefunctionality relating to defining timeslots and may correspond to, forexample, component 808 discussed above. An ASIC for transmitting 1208may provide functionality relating to transmitting signals and maycorrespond to, for example, component 814 discussed above. An ASIC fordefining 1210 may provide functionality relating to defining timeslotsand may correspond to, for example, component 820 discussed above. AnASIC for receiving 1212 may provide functionality relating to receivingsignals as taught herein and may correspond to, for example, component822 discussed above. An ASIC for processing 1214 may providefunctionality relating to processing information as taught herein andmay correspond to, for example, component 826 discussed above. An ASICfor determining/limiting 1216 may provide functionality relating tolimiting transmission as taught herein and may correspond to, forexample, component 828 discussed above. An ASIC for identifying 1218 mayprovide functionality relating to identifying interference as taughtherein and may correspond to, for example, component 830 discussedabove. An ASIC for synchronizing 1220 may provide functionality relatingto synchronizing timeslots as taught herein and may correspond to, forexample, component 832 discussed above.

As noted above, in some aspects these components may be implemented viaappropriate processor components. These processor components may in someaspects be implemented, at least in part, using structure as taughtherein. In some aspects a processor may be adapted to implement aportion or all of the functionality of one or more of these components.In some aspects one or more of the components represented by dashedboxes are optional.

As noted above, the apparatus 1200 may comprise one or more integratedcircuits that provide the functionality of the components illustrated inFIG. 12. For example, in some aspects a single integrated circuit mayimplement the functionality of the illustrated components, while inother aspects more than one integrated circuit may implement thefunctionality of the illustrated components.

In addition, the components and functions represented by FIG. 12, aswell as other components and functions described herein, may beimplemented using any suitable means. Such means also may beimplemented, at least in part, using corresponding structure as taughtherein. For example, in some aspects means for transmitting may comprisea transmitter, means for receiving may comprise a receiver, means fordefining may comprise a timeslot definer, means for processing maycomprise a processor, means for determining may comprise a timeslottransmission limiter, means for limiting may comprise a timeslottransmission limiter, means for identifying may comprise an interferencedeterminer, and means for synchronizing may comprise a timeslotsynchronizer. One or more of such means also may be implemented inaccordance with one or more of the processor components of FIG. 12.

Those of skill in the art would understand that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Those of skill would further appreciate that any of the variousillustrative logical blocks, modules, processors, means, circuits, andalgorithm steps described in connection with the aspects disclosedherein may be implemented as electronic hardware (e.g., a digitalimplementation, an analog implementation, or a combination of the two,which may be designed using source coding or some other technique),various forms of program or design code incorporating instructions(which may be referred to herein, for convenience, as “software” or a“software module”), or combinations of both. To clearly illustrate thisinterchangeability of hardware and software, various illustrativecomponents, blocks, modules, circuits, and steps have been describedabove generally in terms of their functionality. Whether suchfunctionality is implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem. Skilled artisans may implement the described functionality invarying ways for each particular application, but such implementationdecisions should not be interpreted as causing a departure from thescope of the present disclosure.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein may be implementedwithin or performed by an integrated circuit (“IC”), an access terminal,or an access point. The IC may comprise a general purpose processor, adigital signal processor (DSP), an application specific integratedcircuit (ASIC), a field programmable gate array (FPGA) or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, electrical components, optical components,mechanical components, or any combination thereof designed to performthe functions described herein, and may execute codes or instructionsthat reside within the IC, outside of the IC, or both. A general purposeprocessor may be a microprocessor, but in the alternative, the processormay be any conventional processor, controller, microcontroller, or statemachine. A processor may also be implemented as a combination ofcomputing devices, e.g., a combination of a DSP and a microprocessor, aplurality of microprocessors, one or more microprocessors in conjunctionwith a DSP core, or any other such configuration.

It is understood that any specific order or hierarchy of steps in anydisclosed process is an example of a sample approach. Based upon designpreferences, it is understood that the specific order or hierarchy ofsteps in the processes may be rearranged while remaining within thescope of the present disclosure. The accompanying method claims presentelements of the various steps in a sample order, and are not meant to belimited to the specific order or hierarchy presented.

The steps of a method or algorithm described in connection with theaspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module (e.g., including executable instructions and relateddata) and other data may reside in a data memory such as RAM memory,flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a harddisk, a removable disk, a CD-ROM, or any other form of computer-readablestorage medium known in the art. A sample storage medium may be coupledto a machine such as, for example, a computer/processor (which may bereferred to herein, for convenience, as a “processor”) such theprocessor can read information (e.g., code) from and write informationto the storage medium. A sample storage medium may be integral to theprocessor. The processor and the storage medium may reside in an ASIC.The ASIC may reside in user equipment. In the alternative, the processorand the storage medium may reside as discrete components in userequipment. Moreover, in some aspects any suitable computer-programproduct may comprise a computer-readable medium comprising codes (e.g.,executable by at least one computer) relating to one or more of theaspects of the disclosure. In some aspects a computer program productmay comprise packaging materials.

The previous description of the disclosed aspects is provided to enableany person skilled in the art to make or use the present disclosure.Various modifications to these aspects will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other aspects without departing from the scope of thedisclosure. Thus, the present disclosure is not intended to be limitedto the aspects shown herein but is to be accorded the widest scopeconsistent with the principles and novel features disclosed herein.

What is claimed is:
 1. A method for wireless communication, comprising:defining a timeslot for slotted communication; and transmitting, in thetimeslot, data and at least two instances of a control indication,wherein: each instance of the control indication is independentlyencoded and transmitted, each instance of the control indicationcomprises an interference management indication and information thatspecifies a position within the timeslot at which the instance of thecontrol indication is located, the interference management indicationindicates a degree of disadvantage that is based on a measured qualityof service associated with at least one traffic flow established at anapparatus, and the instances of the control indication are separated byat least a portion of the data.
 2. The method of claim 1, wherein: afirst one of the instances of the control indication is transmitted neara beginning of the timeslot; a second one of the instances of thecontrol indication is transmitted near an end of the timeslot; theinformation of the first one of the instances specifies that that thefirst one of the instances is located near the beginning of thetimeslot; and the information of the second one of the instancesspecifies that that the second one of the instances is located near theend of the timeslot.
 3. The method of claim 2, wherein: near a beginningof the timeslot comprises the beginning of the timeslot; and near an endof the timeslot comprises the end of the timeslot.
 4. The method ofclaim 1, wherein: the interference management indication comprises aresource utilization message; and the resource utilization messageindicates a degree to which data reception at the apparatus is beingadversely affected by interfering transmissions from at least onewireless node.
 5. The method of claim 4, wherein the resourceutilization message identifies a channel and requests that at least onewireless node refrain from transmitting on the identified channel orreduce transmission power on the identified channel.
 6. The method ofclaim 1, wherein at least one of the instances of the control indicationcomprises information that facilitates synchronization with thetimeslot.
 7. The method of claim 1, wherein the position is near abeginning or an end of the timeslot.
 8. The method of claim 1, whereinthe slotted communication comprises time division duplex communicationor frequency division duplex communication.
 9. The method of claim 1,wherein the control indication includes a weight indicating a degree towhich the apparatus is disadvantaged.
 10. The method of claim 9, whereinthe weight is based on a ratio of an actual throughput achieved at theapparatus and a desired throughput for the apparatus.
 11. The method ofclaim 9, wherein the weight indicates an extent to which reception ofdata at the apparatus is falling below a desired level.
 12. A method forwireless communication, comprising: measuring quality of serviceassociated with one or more traffic flows established at an apparatus;determining whether the measured quality of service associated with theone or more traffic flows meets a quality of service target; generatingan interference management indication if the quality of service targetis not being met, wherein the interference management indicationindicates a degree of disadvantage that is based on the measured qualityof service; defining a timeslot for slotted communication; andtransmitting, in the timeslot, data and at least two instances of acontrol indication, wherein: each instance of the control indication isindependently encoded and transmitted, each instance of the controlindication comprises information that specifies a position within thetimeslot at which the instance of the control indication is located, andthe control indication comprises the interference management indicationif the quality of service target is not being met.
 13. The method ofclaim 12, wherein the interference management indication requests thatat least one wireless node refrain from transmitting on a channel orreduce transmission power on the channel.
 14. The method of claim 13,wherein the interference management indication is repeated in eachinstance of the control indication.
 15. An apparatus for wirelesscommunication, comprising: a timeslot definer configured to define atimeslot for slotted communication; and a transmitter configured totransmit, in the timeslot, data and at least two instances of a controlindication, wherein: the transmitter is further configured toindependently encode and transmit each instance of the controlindication, each instance of the control indication comprises aninterference management indication and information that specifies aposition within the timeslot at which the instance of the controlindication is located, the interference management indication indicatesa degree of disadvantage that is based on a measured quality of serviceassociated with at least one traffic flow established at the apparatus,and the instances of the control indication are separated by at least aportion of the data.
 16. The apparatus of claim 15, wherein: thetransmitter is further configured to transmit a first one of theinstances of the control indication near a beginning of the timeslot anda second one of the instances of the control indication near an end ofthe timeslot; the information of the first one of the instancesspecifies that that the first one of the instances is located near thebeginning of the timeslot; and the information of the second one of theinstances specifies that that the second one of the instances is locatednear the end of the timeslot.
 17. The apparatus of claim 16, wherein:near a beginning of the timeslot comprises the beginning of thetimeslot; and near an end of the timeslot comprises the end of thetimeslot.
 18. The apparatus of claim 15, wherein: the interferencemanagement indication comprises a resource utilization message; and theresource utilization message indicates a degree to which data receptionat the apparatus is being adversely affected by interferingtransmissions from at least one wireless node.
 19. The apparatus ofclaim 15, wherein at least one of the instances of the controlindication comprises information that facilitates synchronization withthe timeslot.
 20. The apparatus of claim 15, wherein the position isnear a beginning or an end of the timeslot.
 21. The apparatus of claim15, wherein the slotted communication comprises time division duplexcommunication or frequency division duplex communication.
 22. Anapparatus for wireless communication, comprising: a control indicationgenerator configured to measure quality of service associated with oneor more traffic flows established at the apparatus, determine whetherthe measured quality of service associated with the one or more trafficflows meets a quality of service target, and generate a controlindication, wherein the control indication comprises an interferencemanagement indication if the quality of service target is not being met,and wherein the interference management indication indicates a degree ofdisadvantage that is based on the measured quality of service; a timeslot definer configured to define a timeslot for slotted communication;and a transmitter configured to transmit, in the timeslot, data and atleast two instances of the control indication, wherein the transmitteris further configured to independently encode and transmit each instanceof the control indication, and wherein each instance of the controlindication comprises information that specifies a position within thetimeslot at which the instance of the control indication is located. 23.The apparatus of claim 22, wherein the interference managementindication requests that at least one wireless node refrain fromtransmitting on a channel or reduce transmission power on the channel.24. The apparatus of claim 23, wherein the interference managementindication is repeated in each instance of the control indication. 25.An apparatus for wireless communication, comprising: means for defininga timeslot for slotted communication; and means for transmitting, in thetimeslot, data and at least two instances of a control indication,wherein: each instance of the control indication is independentlyencoded and transmitted, each instance of the control indicationcomprises an interference management indication and information thatspecifies a position within the timeslot at which the instance of thecontrol indication is located, the interference management indicationindicates a degree of disadvantage that is based on a measured qualityof service associated with at least one traffic flow established at theapparatus, and the instances of the control indication are separated byat least a portion of the data.
 26. The apparatus of claim 25, wherein:the means for transmitting transmits a first one of the instances of thecontrol indication near a beginning of the timeslot and a second one ofthe instances of the control indication near an end of the timeslot; theinformation of the first one of the instances specifies that that thefirst one of the instances is located near the beginning of thetimeslot; and the information of the second one of the instancesspecifies that that the second one of the instances is located near theend of the timeslot.
 27. The apparatus of claim 26, wherein: near abeginning of the timeslot comprises the beginning of the timeslot; andnear an end of the timeslot comprises the end of the timeslot.
 28. Theapparatus of claim 25, wherein: the interference management indicationcomprises a resource utilization message; and the resource utilizationmessage indicates a degree to which data reception at the apparatus isbeing adversely affected by interfering transmissions from at least onewireless node.
 29. The apparatus of claim 25, wherein at least one ofthe instances of the control indication comprises information thatfacilitates synchronization with the timeslot.
 30. The apparatus ofclaim 25, wherein the position is near a beginning or an end of thetimeslot.
 31. The apparatus of claim 25, wherein the slottedcommunication comprises time division duplex communication or frequencydivision duplex communication.
 32. An apparatus for wirelesscommunication, comprising: means for measuring quality of serviceassociated with one or more traffic flows established at the apparatus;means for determining whether the measured quality of service associatedwith the one or more traffic flows meets a quality of service target;means for generating an interference management indication if thequality of service target is not being met, wherein the interferencemanagement indication indicates a degree of disadvantage that is basedon the measured quality of service; means for defining a timeslot forslotted communication; and means for transmitting, in the timeslot, dataand at least two instances of a control indication, wherein: eachinstance of the control indication is independently encoded andtransmitted, each instance of the control indication comprisesinformation that specifies a position within the timeslot at which theinstance of the control indication is located, and the controlindication comprises the interference management indication if thequality of service target is not being met.
 33. The apparatus of claim32, wherein the interference management indication requests that atleast one wireless node refrain from transmitting on a channel or reducetransmission power on the channel.
 34. The apparatus of claim 33,wherein the interference management indication is repeated in eachinstance of the control indication.
 35. A computer-program product forwireless communication, comprising: a computer-readable storage deviceencoded with codes executable by at least one computer to: define atimeslot for slotted communication; and transmit, in the timeslot, dataand at least two instances of a control indication, wherein: eachinstance of the control indication is independently encoded andtransmitted, each instance of the control indication comprises aninterference management indication and information that specifies aposition within the timeslot at which the instance of the controlindication is located, the interference management indication indicatesa degree of disadvantage that is based on a measured quality of serviceassociated with at least one traffic flow established at an apparatus,and the instances of the control indication are separated by at least aportion of the data.
 36. An access point for wireless communication,comprising: an antenna; a timeslot definer configured to define atimeslot for slotted communication; and a transmitter configured totransmit, in the timeslot, data and at least two instances of a controlindication via the antenna, wherein: the transmitter is furtherconfigured to independently encode and transmit each instance of thecontrol indication, each instance of the control indication comprises aninterference management indication and information that specifies aposition within the timeslot at which the instance of the controlindication is located, the interference management indication indicatesa degree of disadvantage that is based on a measured quality of serviceassociated with at least one traffic flow established at the accesspoint, and the instances of the control indication are separated by atleast a portion of the data.
 37. An access terminal for wirelesscommunication, comprising: a timeslot definer configured to define atimeslot for slotted communication; a transmitter configured totransmit, in the timeslot, data and at least two instances of a controlindication, wherein: the transmitter is further configured toindependently encode and transmit each instance of the controlindication, each instance of the control indication comprises aninterference management indication and information that specifies aposition within the timeslot at which the instance of the controlindication is located, the interference management indication indicatesa degree of disadvantage that is based on a measured quality of serviceassociated with at least one traffic flow established at the accessterminal, and the instances of the control indication are separated byat least a portion of the data; and a user interface configured toprovide data to be transmitted by the transmitter.
 38. A method forwireless communication, comprising: defining a receive timeslot forslotted communication; and receiving, during the receive timeslot,signals associated with a transmit timeslot, wherein: the transmittimeslot comprises data and at least two instances of a controlindication; each instance of the control indication is independentlyencoded and transmitted; each instance of the control indicationcomprises an interference management indication and information thatspecifies a position within the timeslot at which the instance of thecontrol indication is located; the interference management indicationindicates a degree of disadvantage that is based on a measured qualityof service associated with at least one traffic flow established at anapparatus; and the instances of the control indication are separated byat least a portion of the data.
 39. The method of claim 38, furthercomprising processing the signals received over an entirety of thereceive timeslot to extract at least one of the instances of the controlindication for the transmit timeslot.
 40. The method of claim 38,wherein: the instances of the control indication for the transmittimeslot are near a beginning of the transmit timeslot and near an endof the transmit timeslot; the information of a first one of theinstances specifies that that the first one of the instances is locatednear the beginning of the transmit timeslot; and the information of asecond one of the instances specifies that that the second one of theinstances is located near the end of the transmit timeslot.
 41. Themethod of claim 40, wherein: near a beginning of the transmit timeslotcomprises the beginning of the transmit timeslot; and near an end of thetransmit timeslot comprises the end of the transmit timeslot.
 42. Themethod of claim 38, wherein: the interference management indicationcomprises a resource utilization message; and the resource utilizationmessage indicates a degree to which data reception at the apparatus isbeing adversely affected by interfering transmissions.
 43. The method ofclaim 38, further comprising determining, based on at least one of theinstances of the control indication, whether to limit transmissionsduring at least a portion of a subsequent timeslot.
 44. The method ofclaim 38, further comprising: identifying, based on at least one of theinstances of the control indication, a portion of a subsequent timeslotsubject to interference; and limiting transmissions during theidentified portion of the subsequent timeslot.
 45. The method of claim38, wherein at least one of the instances of the control indicationcomprises information that facilitates synchronization to the transmittimeslot.
 46. The method of claim 38, further comprising synchronizingto the transmit timeslot based on at least one of the instances of thecontrol indication.
 47. The method of claim 38, further comprisingsynchronizing to the transmit timeslot based on the information.
 48. Themethod of claim 47, wherein the position is near a beginning or an endof the transmit timeslot.
 49. The method of claim 38, wherein thetransmit timeslot and the receive timeslot are not synchronized in time.50. The method of claim 38, wherein the slotted communication comprisestime division duplex communication or frequency division duplexcommunication.
 51. An apparatus for wireless communication, comprising:a timeslot definer configured to define a receive timeslot for slottedcommunication; and a receiver configured to receive, during the receivetimeslot, signals associated with a transmit timeslot, wherein: thetransmit timeslot comprises data and at least two instances of a controlindication; each instance of the control indication is independentlyencoded and transmitted; each instance of the control indicationcomprises an interference management indication and information thatspecifies a position within the timeslot at which the instance of thecontrol indication is located; the interference management indicationindicates a degree of disadvantage that is based on a measured qualityof service associated with at least one traffic flow established atanother apparatus; and the instances of the control indication areseparated by at least a portion of the data.
 52. The apparatus of claim51, further comprising a processor configured to process the signalsreceived over an entirety of the receive timeslot to extract at leastone of the instances of the control indication for the transmittimeslot.
 53. The apparatus of claim 51, wherein: the instances of thecontrol indication for the transmit timeslot are near a beginning of thetransmit timeslot and near an end of the transmit timeslot; theinformation of a first one of the instances specifies that that thefirst one of the instances is located near the beginning of the transmittimeslot; and the information of a second one of the instances specifiesthat that the second one of the instances is located near the end of thetransmit timeslot.
 54. The apparatus of claim 53, wherein: near abeginning of the transmit timeslot comprises the beginning of thetransmit timeslot; and near an end of the transmit timeslot comprisesthe end of the transmit timeslot.
 55. The apparatus of claim 51,wherein: the interference management indication comprises a resourceutilization message; and the resource utilization message indicates adegree to which data reception at the other apparatus is being adverselyaffected by interfering transmissions.
 56. The apparatus of claim 51,further comprising a transmission limiter configured to determine, basedon at least one of the instances of the control indication, whether tolimit transmissions during at least a portion of a subsequent timeslot.57. The apparatus of claim 51, further comprising: an interferencedeterminer configured to identify, based on at least one of theinstances of the control indication, a portion of a subsequent timeslotsubject to interference; and a transmission limiter configured to limittransmissions during the identified portion of the subsequent timeslot.58. The apparatus of claim 51, wherein at least one of the instances ofthe control indication comprises information that facilitatessynchronization to the transmit timeslot.
 59. The apparatus of claim 51,further comprising a timeslot synchronizer configured to synchronize tothe transmit timeslot based on at least one of the instances of thecontrol indication.
 60. The apparatus of claim 51, further comprising atimeslot synchronizer configured to synchronize to the transmit timeslotbased on the information.
 61. The apparatus of claim 60, wherein theposition is near a beginning or an end of the transmit timeslot.
 62. Theapparatus of claim 51, wherein the transmit timeslot and the receivetimeslot are not synchronized in time.
 63. The apparatus of claim 51,wherein the slotted communication comprises time division duplexcommunication or frequency division duplex communication.
 64. Anapparatus for wireless communication, comprising: means for defining areceive timeslot for slotted communication; and means for receiving,during the receive timeslot, signals associated with a transmittimeslot, wherein: the transmit timeslot comprises data and at least twoinstances of a control indication; each instance of the controlindication is independently encoded and transmitted; each instance ofthe control indication comprises an interference management indicationand information that specifies a position within the timeslot at whichthe instance of the control indication is located; the interferencemanagement indication indicates a degree of disadvantage that is basedon a measured quality of service associated with at least one trafficflow established at another apparatus; and the instances of the controlindication are separated by at least a portion of the data.
 65. Theapparatus of claim 64, further comprising means for processing thesignals received over an entirety of the receive timeslot to extract atleast one of the instances of the control indication for the transmittimeslot.
 66. The apparatus of claim 64, wherein: the instances of thecontrol indication for the transmit timeslot are near a beginning of thetransmit timeslot and near an end of the transmit timeslot; theinformation of a first one of the instances specifies that that thefirst one of the instances is located near the beginning of the transmittimeslot; and the information of a second one of the instances specifiesthat that the second one of the instances is located near the end of thetransmit timeslot.
 67. The apparatus of claim 66, wherein: near abeginning of the transmit timeslot comprises the beginning of thetransmit timeslot; and near an end of the transmit timeslot comprisesthe end of the transmit timeslot.
 68. The apparatus of claim 64,wherein: the interference management indication comprises a resourceutilization message; and the resource utilization message indicates adegree to which data reception at the other apparatus is being adverselyaffected by interfering transmissions.
 69. The apparatus of claim 64,further comprising means for determining, based on at least one of theinstances of the control indication, whether to limit transmissionsduring at least a portion of a subsequent timeslot.
 70. The apparatus ofclaim 64, further comprising: means for identifying, based on at leastone of the instances of the control indication, a portion of asubsequent timeslot subject to interference; and means for limitingtransmissions during the identified portion of the subsequent timeslot.71. The apparatus of claim 64, wherein at least one of the instances ofthe control indication comprises information that facilitatessynchronization to the transmit timeslot.
 72. The apparatus of claim 64,further comprising means for synchronizing to the transmit timeslotbased on at least one of the instances of the control indication. 73.The apparatus of claim 64, further comprising means for synchronizing tothe transmit timeslot based on the information.
 74. The apparatus ofclaim 73, wherein the position is near a beginning or an end of thetransmit timeslot.
 75. The apparatus of claim 64, wherein the transmittimeslot and the receive timeslot are not synchronized in time.
 76. Theapparatus of claim 64, wherein the slotted communication comprises timedivision duplex communication or frequency division duplexcommunication.
 77. A computer-program product for wirelesscommunication, comprising: a computer-readable storage device encodedwith codes executable by at least one computer to: define a receivetimeslot for slotted communication; and receive, during the receivetimeslot, signals associated with a transmit timeslot, wherein: thetransmit timeslot comprises data and at least two instances of a controlindication; each instance of the control indication is independentlyencoded and transmitted; each instance of the control indicationcomprises an interference management indication and information thatspecifies a position within the timeslot at which the instance of thecontrol indication is located; the interference management indicationindicates a degree of disadvantage that is based on a measured qualityof service associated with at least one traffic flow established at anapparatus; and the instances of the control indication are separated byat least a portion of the data.
 78. An access point for wirelesscommunication, comprising: an antenna; a timeslot definer configured todefine a receive timeslot for slotted communication; and a receiverconfigured to receive, via the antenna and during the receive timeslot,signals associated with a transmit timeslot, wherein: the transmittimeslot comprises data and at least two instances of a controlindication; each instance of the control indication is independentlyencoded and transmitted; each instance of the control indicationcomprises an interference management indication and information thatspecifies a position within the timeslot at which the instance of thecontrol indication is located; the interference management indicationindicates a degree of disadvantage that is based on a measured qualityof service associated with at least one traffic flow established at anapparatus; and the instances of the control indication are separated byat least a portion of the data.
 79. An access terminal for wirelesscommunication, comprising: a timeslot definer configured to define areceive timeslot for slotted communication; a receiver configured toreceive, during the receive timeslot, signals associated with a transmittimeslot, wherein: the transmit timeslot comprises data and at least twoinstances of a control indication; each instance of the controlindication is independently encoded and transmitted; each instance ofthe control indication comprises an interference management indicationand information that specifies a position within the timeslot at whichthe instance of the control indication is located; the interferencemanagement indication indicates a degree of disadvantage that is basedon a measured quality of service associated with at least one trafficflow established at an apparatus; and the instances of the controlindication are separated by at least a portion of the data; and a userinterface configured to output data received by the receiver.